The UN estimates that 400,000 people in this remote region of the DRC have fled their homes as the LRA – once based in Uganda – responded to attacks from Ugandan and Congolese troops by striking out against civilians. Led by Joseph Kony, who is wanted by the international criminal court, LRA fighters have looted towns and villages, abducted hundreds of children, and raped and killed people.

"We are talking about tactics of violence aimed at instilling fear in the people," said Luis Encinas, the co-ordinator of Médecins sans Frontières (MSF) operations in central Africa. "Our patients have told us the most brutal stories – about children who are forced to kill their parents and people burnt alive inside their homes."

Civilians increasingly have come under threat since September last year, when Congolese and Ugandan forces moved to crush the last remnants of the LRA after they were driven out of Uganda. The fighting has spilled over into Sudan and the Central African Republic. In response to the LRA's terror tactics, civilians have fled to the main towns, where they are being helped by the local population as best they can and by relief groups such as MSF and the International Committee of the Red Cross (ICRC).

Towns such as Gangala and Banda have become enclaves for 20,000 displaced people each as outlying fields and villages are deserted. The humanitarian crisis in the Haut-Uélé district, in north-eastern DRC bears some parallels with that in eastern Congo, where government forces are battling Hutu rebel groups who fled Rwanda after the 1994 genocide in which 800,000 Tutsis were slaughtered.

In both regions, the violence against civilians has been a consequence of military attempts to crush an elusive and ruthless rebel force. But the situation in the north has received less media attention than eastern Congo. MSF is making an urgent appeal to the UN and other relief agencies to redeploy staff from the central town of Dungu to provide aid in outlying areas.

"We are saying to other groups: just stay in the outlying areas beyond the main town of Dungu," said Katharine Derderian, MSF humanitarian affairs adviser, who was in northern Congo in July. "Even such a small step could make a huge difference."

In several places, such as Dingila or Niangara, MSF is the only group present despite security concerns. This lack

of security and the absence of roads in some isolated areas means MSF has had to use planes to bring in supplies.

"Delivering humanitarian aid to the people of this region is of course a challenge," Encinas said, "but we believe much more can and must be done to address the consequences of war on the population. Humanitarian organisations should urgently address people's needs in areas that are most affected by the fighting and have so far been neglected."

• This article was amended on 16 October 2009. The original standfirst said that 40,000 people had been displaced. This has been corrected.

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